The General Hospital star shared a video on Instagram Thursday of Harrison dancing with an emotional caption about love and loss. "Sometimes I feel like a pinned butterfly. There's no second chance. There's no see-him-again. There's no nothing. He's not coming back. It's final," she wrote.
"But life goes on. How do I spend the rest of my own without Harrison in it? What does it mean to be "all right" after the death of your child, your blood? The pain will never go away. Today is Harrison's birthdate. I had the privilege to know him for 27 incredible years," she added.
In addition to the grief, Kristina spotlighted some of the best things about Harrison — and how they impacted the people around him. "Harrison was larger than life, but beneath his commanding presence was vulnerability and compassion," she said.
"He understood his own defects and worked hard to turn them around, to strengthen his positive attributes. He was a good listener and stood up for others when they couldn't speak for themselves. He is missed. Happy Birthday, Harrison."
She concluded on a comforting note for others who are mourning the loss of a child. "To all bereaved parents: May you find peace. Let's stick around and see what's in store for our extraordinary lives."
Harrison, whose father is General Hospital's Jack Wagner, died in June. Per a report from the Los Angeles Medical Examiner's Office obtained by PEOPLE, Harrison was found in a local parking lot on Monday and was pronounced dead at the scene. His cause of death was deferred at the time.
His family later revealed that Harrison "ultimately lost his battle with addiction." The Wagner family created the Harrison Wagner Scholarship Fund just a week after Harrison's passing, which partnered with New Life House Recovery Community — an organization of sober living facilities for men in the Los Angeles area.
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On Twitter Thursday, Kristan added an additional photo of Harrison. "Loving son, Harrison Hale Wagner, Dec 1, 1994 [to] June 6, 2022," she tweeted. "This picture was taken one year ago. It was a happy birthday. I'm so grateful beyond words he was in my life."
If you or someone you know is struggling with substance abuse, please contact the SAMHSA helpline at 1-800-662-HELP.